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Title: Inertial-Fusion-Related Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave

Abstract

Experiments studying the compression and unstable growth of a dense spherical bubble in a gaseous medium subjected to a strong planar shock wave (2.8 < M < 3.4) are performed in a vertical shock tube. The test gas is initially contained in a free-falling spherical soap-film bubble, and the shocked bubble is imaged using planar laser diagnostics. Concurrently, simulations are carried out using a compressible hydrodynamics code in r-z axisymmetric geometry.Experiments and computations indicate the formation of characteristic vortical structures in the post-shock flow, due to Richtmyer-Meshkov and Kelvin-Helmholtz instabilities, and smaller-scale vortices due to secondary effects. Inconsistencies between experimental and computational results are examined, and the usefulness of the current axisymmetric approach is evaluated.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2]
  1. University of Wisconsin-Madison (United States)
  2. Lawrence Livermore National Laboratory (United States)
Publication Date:
OSTI Identifier:
20854065
Resource Type:
Journal Article
Resource Relation:
Journal Name: Fusion Science and Technology; Journal Volume: 47; Journal Issue: 4; Other Information: Copyright (c) 2006 American Nuclear Society (ANS), United States, All rights reserved. http://epubs.ans.org/; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AXIAL SYMMETRY; BUBBLES; COMPUTERIZED SIMULATION; GEOMETRY; HELMHOLTZ INSTABILITY; HYDRODYNAMICS; ICF DEVICES; INERTIAL CONFINEMENT; INERTIAL FUSION DRIVERS; LASERS; PLASMA SIMULATION; SHOCK TUBES; SHOCK WAVES; SPHERICAL CONFIGURATION; VORTICES

Citation Formats

Niederhaus, John, Ranjan, Devesh, Anderson, Mark, Oakley, Jason, Bonazza, Riccardo, and Greenough, Jeff. Inertial-Fusion-Related Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave. United States: N. p., 2005. Web.
Niederhaus, John, Ranjan, Devesh, Anderson, Mark, Oakley, Jason, Bonazza, Riccardo, & Greenough, Jeff. Inertial-Fusion-Related Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave. United States.
Niederhaus, John, Ranjan, Devesh, Anderson, Mark, Oakley, Jason, Bonazza, Riccardo, and Greenough, Jeff. 2005. "Inertial-Fusion-Related Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave". United States. doi:.
@article{osti_20854065,
title = {Inertial-Fusion-Related Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave},
author = {Niederhaus, John and Ranjan, Devesh and Anderson, Mark and Oakley, Jason and Bonazza, Riccardo and Greenough, Jeff},
abstractNote = {Experiments studying the compression and unstable growth of a dense spherical bubble in a gaseous medium subjected to a strong planar shock wave (2.8 < M < 3.4) are performed in a vertical shock tube. The test gas is initially contained in a free-falling spherical soap-film bubble, and the shocked bubble is imaged using planar laser diagnostics. Concurrently, simulations are carried out using a compressible hydrodynamics code in r-z axisymmetric geometry.Experiments and computations indicate the formation of characteristic vortical structures in the post-shock flow, due to Richtmyer-Meshkov and Kelvin-Helmholtz instabilities, and smaller-scale vortices due to secondary effects. Inconsistencies between experimental and computational results are examined, and the usefulness of the current axisymmetric approach is evaluated.},
doi = {},
journal = {Fusion Science and Technology},
number = 4,
volume = 47,
place = {United States},
year = 2005,
month = 5
}
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